Are they really having any issue getting people to upgrade? At least here in Canada, carriers harass everyone to upgrade with deals where you can get a new phone for $0 once your contract is up to keep you renewing your contract.

My non-techie parents pretty much always get the latest non-Pro iPhone every couple years because their carrier calls them and practically begs them to take a new phone.

It's extremely rare to see anyone with a phone older than like 4 years.